140) A 15 year old boy with history of Cystic Fibrosis presents to the Emergency room with complaints of severe right lower quadrant abdominal pain. He also gives a history of nausea and vomiting for the past 8 hours. On examination, his temperature is 102F and he has right lower quadrant tenderness at McBurney’s Point. CT scan of the abdomen revealed calcified appendicolith within the dilated, fluid-filled appendix and infiltration of the surrounding retroperitoneal fat. The patient is scheduled for Appendicectomy. However, pre-operative labs reveal an abnormal result that would put the patient at an increased risk of bleeding from surgery. The patient is referred for medical clearance. Which of the following is most likely to be abnormal in this patient?
A) Platelet count
B) Prothrombin time
C) Partial Thromboplastin Time
D) Both Prothrombin time and Partial Thromboplastin time
E) Bleeding time
Archer USMLE Step 3 Blog 
bleeding time fat soluble vitamins ?
b – prothrombin time
D) Both Prothrombin time and Partial Thromboplastin time
b)pt, because vit K dependant, and cystic fibrosis causes vit def. due to malabsorption
D…..there is effect on both PT and PTT in patient with vit…k deficiency.First there is elevation of PT and then PTT….pts with cystic fibrosis have vit k deficiency
bbb
D- Kaplan Notes 2011, p.302
Vitamin K deficiency results in a hypocoagulable state resulting in a reduction of coagulation factors, increasing PTT and an increase in PT and INR level. The other disease that results in a similar situation is Crohn disease.
There’s an important tip for the exam that you need to know and that is excess vitamin E, garlic, fish oil and gingko bilboa can also interfere with vitamin K absorption and result in an excess PTT, PT and INR leading to bleeding.
100% Dr.Najmi it’s D
D.
B is correct answer.
Measurements of serum PT and PTT: Patients with VK deficiency tend to have an elevated PT and a normal aPTT.[16] Both PT and aPTT can be elevated in more severe deficiency states.
http://emedicine.medscape.com/article/126354-workup
Be ware that the question is “what is most likely to be abnormal?” rather than “which could be abnormal?” So the best answer is B, PT.
Correct me if I’m wrong.
bravo doctor Z